@mixin border-1px($color){
    position: relative;
    &::after{
        display: block;
        position: absolute;
        left: 0;
        bottom: 0;
        content: '';
        width: 100%;
        border-top: 1px solid $color;
    }
}
@mixin border-none(){
    &::after{
        display: none;
    }
}
@mixin bg-image($url){
    background-image: url($url+'@2x.png');
    @media(-webkit-min-device-pixel-ratio:3),(min-device-pixel-ratio:3){
         background-image: url($url+'@3x.png');
    }
}
